Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06126 (CD1a)
 2,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

M cells are found in intestinal follicle associated epithelium. Studies into the physiological and pathological roles of human M cells have been hampered by the lack of well-substantiated, specific markers for these cells. A critical literature review suggests the following molecules may potentially serve as such markers: CK7, FcaR (CD89), S100, CD1a, CD21, CD23, sialyl Lewis A, and cathepsin E. Normal ileum, appendix and colorectum were studied using paraffin-embedded, formalin-fixed tissue and immunohistochemistry for these 8 markers. Cathepsin E immunohistochemistry was also performed on cases of colorectal adenocarcinoma, colorectal adenoma, colorectal hyperplastic/metaplastic polyp, lymphocytic colitis, collagenous colitis, pseudomembranous colitis and active ulcerative colitis. Of the 8 markers tested, only cathepsin E appeared to be specific to follicle associated epithelium (expressed by cells with and without M cell morphology) and follicular crypt epithelium; this specificity was limited to the colorectum. Focal epithelial expression of cathepsin E was seen in adenocarcinoma, adenoma, hyperplastic/metaplastic polyp, ulcerative colitis and pseudomembranous colitis. In conclusion, cathepsin E is a specific marker of normal colorectal follicle associated epithelium and follicular crypt epithelium though is not specific to M cells within these compartments. None of the other 7 markers studied is exclusively expressed by human M cells.
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PMID:An immunohistochemical study and review of potential markers of human intestinal M cells. 1277 11

An increase in S100 protein-positive cells has been reported in inflammatory bowel diseases, mainly Crohn disease. These cells were interpreted as myeloid-derived dendritic cells, chiefly in follicular areas. We were prompted to assess the nature of these cells in interfollicular areas of inflamed colonic mucosa in ulcerative colitis and study their involvement in tumor necrosis factor alpha production, the main inflammatory cytokine in ulcerative colitis. The number and distribution of cells expressing S100 protein, nerve growth factor receptor, CD68, CD1a, CD83, and calretinin were studied in samples from 16 patients with active ulcerative colitis using simple and double immunohistochemistry. Then, the localization in S100 protein-positive cells of (1) tumor necrosis factor alpha, (2) its sheddase A disintegrin and metalloprotease-17, and (3) the receptors TNFR1 was assessed using double immunofluorescence followed by confocal microscopy. In active ulcerative colitis, there was an increased number in S100 protein-positive cells in interfollicular areas of colonic mucosa compared with quiescent ulcerative colitis, nonulcerative colitis, or normal mucosa. All S100 protein-positive cells ensheathed calretinin-positive axons, indicating their Schwann cell origin. No CD1a- or CD83-positive dendritic cells were detected. Double immunofluorescence studies showed that in normal colon, Schwann cells of the mucosa and submucosal plexuses weakly expressed A disintegrin and metalloprotease-17 but did not express tumor necrosis factor alpha. By contrast, in active ulcerative colitis, they expressed both A disintegrin and metalloprotease-17 and tumor necrosis factor alpha. Schwann cells as well as calretinin-positive axons strongly expressed TNFR1. This study shows (1) a Schwann cell proliferation in the inflamed colonic mucosa during active ulcerative colitis and (2) that Schwann cells produce tumor necrosis factor alpha. Tumor necrosis factor alpha is thus likely to stimulate Schwann cell proliferation through an autocrine/paracrine mechanism.
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PMID:In situ evidence of involvement of Schwann cells in ulcerative colitis: autocrine and paracrine signaling by A disintegrin and metalloprotease-17-mediated tumor necrosis factor alpha production. 1937 60